Continuously maintaining acceptable levels of respirable dust and airborne crystalline silica to which personnel are exposed during overburden and rock drilling operations at surface mining and construction sites can be an ongoing challenge. “Breathing excessive amounts of crystalline silica during rock drilling, can cause a serious fatal respiratory disease called “silicosis”, according to the National Institute for Occupational Safety and Health (NIOSH).”
Numerous control and management techniques have been researched, developed, and implemented over the years to minimize the levels of respirable dust and crystalline silica to which drill operators are exposed. One area of focus is managing air quality inside enclosed operator cabs of overburden drills by supplying the cleanest air available into the cab and then maintaining positive pressure of filtered air inside the cab. This may be problematic in overburden and rock drilling operations considering that elevated levels of contaminates may exist in the outside air to be introduced into the drill cab through the air handling system.
Research and observations have concluded that the level of airborne contaminants associated with surface mining and construction (earth moving) is quite often related to the height above the ground, with the cleanest air most frequently found at greater heights. Air filtering systems for enclosed cabs on mobile equipment used in these operations, including overburden drills, are often located on top of the operator's cab to take advantage of height. Overburden drills, by the nature of their design and operation offer potential to access even cleaner air found at significantly greater heights by utilizing the height of the mast for the inlet to the air system. However, effectively locating the air inlet point high up on the drill mast requires a design that overcomes the constraints imposed with raising and lowering the drill mast and therefore avoids any obstruction or interference with the drilling operations.
This particular invention, the Fresh Air Intake System for Overburden Drills, is designed to access cleaner air at greater heights by locating the air intake point toward the top of the drill mast resulting in a much greater height above the ground. The system also includes air filter and pressure blower/circulating fan assemblies, whereby filtered intake air is supplied into the enclosed operator's cab under positive pressure.